Engine components (such as cylinders and valves) may degrade with age in various ways. For example, sludged throttle bodies can restrict airflow. As another example, soot deposit on spark plugs can increase knock limitation while soot build-up on particulate filters can degrade engine performance due to increased back-pressure. While engine controls may be adapted to adjust engine operation based on the changing range of component performances, the range that can be compensated for may be fairly narrow. Even within that range, there may be a limited number of adjustments that can be performed. As a result, either extensive cleaning or intermittent replacement of engine components may be required to maintain acceptable engine performance for an extended amount of time. However, this may add unacceptable costs to vehicle operation, in addition to warranty issues. Overall, a vehicle customer satisfaction may be reduced.
The inventors herein have recognized that ionized air can be advantageously used to reduce engine component degradation. Specifically, a service technician may be able to send an ion-rich air stream through the air injection system of an engine to oxidize and remove organic matter from the engine system. In one example, a method for reducing engine component degradation comprises: introducing ionized air into an engine cylinder while rotating the engine unfueled; and oxidizing organic matter in the cylinder using the introduced ionized air. In this way, engine performance degradation due to accumulation of soot and sludge on various components can be reduced.
For example, during non-combusting conditions, a service technician may couple an external source of ionized air to an engine intake, specifically, to an air intake throttle or to an air intake system. Ionized air may then be blown from the air source through the engine intake to engine cylinders where cylinder organic matter (e.g., hydrocarbons and oil) may be oxidized. The ionized air may then be flowed from the cylinder to the engine exhaust system where exhaust organic matter (e.g., hydrocarbons, oil, soot, etc.) may be oxidized. The service technician may concurrently connect a service tool to a diagnostics port (e.g., OBD port) of the vehicle. When connected to the diagnostics port, the service tool may be communicatively coupled to a vehicle control system, allowing operator input received via the service tool to be relayed into engine powertrain commands. For example, based on the operator input, while flowing the ionized air, an intake throttle may be fully opened, an EGR valve may be fully opened, and/or intake and exhaust cams may be advanced. In addition, the engine may be rotated or spun, unfueled, to allow for ionized air to be delivered to all engine cylinders.
In this way, engine components may be cleaned and refurbished in a more cost-effective and simpler manner. By streaming ionized air into the engine, organic matter such as oil, sludge, hydrocarbons and soot can be oxidized and easily removed from the engine system. By concurrently rotating the engine, unfueled, ionized air can be delivered to each engine cylinder, enabling a more complete cleaning of the engine. By not requiring the engine components to be disassembled for the cleaning, the cost, labor, and time required to refurbish the engine is significantly reduced. By using ionized air to periodically tune-up the engine, engine performance may be improved and component life may be increased. Overall, engine warranty may be improved.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.